Syphilis is a generally sexually transmitted and multisystem disease caused by the spirochete Treponema pallidum. All of the organs of the body may be involved during the course of the disease. Neurosyphilis is a clinical form of syphilis with the central nervous system (CNS) involvement. While primarily meningeal and vascular structures are involved in early neurosyphilis, a parenchymal affection of the brain and spinal cord emerges at later stages of neurosyphilis. It presents with symptoms of meningitis, meningovasculitis and parenchymal neurosyphilis (presenting as tabes dorsalis and general paresis). Clinically, it can mimic a variety of psychiatric disorders such as depression, psychosis, mania, delirium, personality changes and dementia. During its progression making presentations similar to many systemic or neuropsychiatric diseases, syphilis is defined as "great imitator". Nowadays, neurosyphilis is a rare disease as a result of the widespread use of antibiotics that must be kept in mind in the differential diagnosis of neurological and psychiatric disorders. In this article, three neurosyphilis cases with different psychiatric presentations are reported and literature relevant to syphilis are reviewed.